trapFocusWhenever  
  fun Tag<HTMLElement>.trapFocusWhenever(condition: Flow<Boolean>, restoreFocus: Boolean = true, setInitialFocus: InitialFocus = TryToSet)
This variant of trapFocusInMountpoint allows to reactively trap a focus based on a conditional Flow of Boolean. This should be applied in all situations, where the DOM subtree of the trap is not inside a mount-point, but only activated or disabled by some Flow.
Parameters
condition
some boolean Flow that will enable the trap only on `true` values.
restoreFocus 
sets the focus back to the element that had the focus before the container with the trap was entered.
setInitialFocus  
will automatically focus the first element of the container or that one, which has been     tagged by setInitialFocus function if the InitialFocus value has focus=true.